As it is written in *Celestial Craftsmanship*: All things possess a spirit, and all can be refined.
These were not empty words.
When subjected to power of a sufficient level, almost anything could be refined to extract "Spiritual Materials"—substances that exist on the cusp of observable and unobservable matter.
This was true for mountains and ores, for the essence of plants and trees, and even, in theory, for the flesh and blood of living beings—not to mention their scattered emotions and willpower.
*Celestial Craftsmanship* never shied away from this, recording such techniques in exhaustive detail.
Of course, not all Spiritual Materials were suitable for use.
The materials had to align with the inherent "principle" and "nature" of the object being refined.
Forcibly integrating an incompatible substance would, at best, yield poor results for twice the effort. At worst, it could destroy the artifact and injure the smith.
